A sauna (pronounced /ˈsɑunɑ/), is a small room or house designed as a place to experience dry or wet heat sessions, or an establishment with one or more of these and auxiliary facilities. These facilities derive from the Finnish sauna. The word "sauna" is also used figuratively to describe an unusually hot or humid environment.

A sauna session can be a social affair in which the participants disrobe and sit or recline in temperatures of over 80 °C (176 °F). This induces relaxation and promotes sweating.

Saunas can be divided into two basic styles: Conventional saunas that warm the air or infrared saunas that warm objects. Infrared saunas may use various materials in their heating area such as charcoal, active carbon fibers, and other materials.

History

First saunas

The oldest known saunas were pits dug in a slope in the ground and primarily used as dwellings in winter. The sauna featured a fireplace where stones were heated to a high temperature. Water was thrown over the hot stones to produce steam and to give a sensation of increased heat. This would raise the apparent temperature so high that people could take off their clothes. The first Finnish saunas are what nowadays are called savusaunas, or smoke saunas. These differed from present-day saunas in that they were heated by heating a pile of rocks called kiuas by burning large amounts of wood about 6 to 8 hours, and then letting the smoke out before enjoying the löyly, or sauna heat. A properly heated "savusauna" gives heat up to 12 hours. These are still used in present-day Finland by some enthusiasts, but usually only on special occasions such as Christmas, New Year's, Easter, and juhannus (Midsummer).